As one of the methods for inspecting and observing a biological sample extracted from a human body, experimental animal, or the like, a method is known in which a thin section is prepared from an embedding block in which the biological sample is embedded by an embedding agent, dye processing is performed on the thin section, and thus, the biological sample is observed.
In the related art, an operation of preparing the thin section is performed manually by an experienced operator using a sharp and thin cutting blade. However, in recent years, an automatic thin-cutting device capable of automatically performing the operation of preparing the thin section has begun to be in use. According to this automatic thin-cutting device, it is possible to continuously prepare the thin section without imposing a burden on the operator.
In the above-described automatic thin-cutting device, the cutting blade and the embedding block are moved relative to each other in a predetermined feeding direction, the embedding block is cut at a thickness of several micrometers (for example, 3 μm to 5 μm), and thus, the thin section can be obtained.
Here, since the thin section obtained by the cutting is cut at an extremely thin thickness, wrinkling or curling easily occurs on the thin section. Accordingly, the thin section obtained by the cutting is floated on a water surface to remove the wrinkling or the curling (spreading process).
Thereafter, the thin section floating on the water surface is scooped by a substrate such as a slide glass, and is placed on the substrate. Accordingly, a thin section sample can be prepared.
In the above-described process of cutting the thin section, in order to decrease a load applied to the biological sample due to the thin-cutting, generally, a method in which the embedding block is cut by the cutting blade having a draw angle is known. In addition, the draw angle is an angle in which an axis line orthogonal to the feeding directions of the cutting blade and the embedding block and an extension direction of the edge of the cutting blade cross each other at an acute angle on a cutting surface formed by the cutting blade.
In addition, in the above-described spreading process, when the thin section is scooped by the substrate and is placed on the substrate, the direction of the thin section with respect to the substrate is varied on the water surface. Accordingly, a portion of the thin section scooped by the substrate protrudes from the substrate, and may not be placed on the substrate.
Therefore, for example, Patent Document 1 discloses a configuration which includes a relay body having a fixing surface to which a thin section is detachably fixed, a holding portion holding the relay body, and moving and rotating means having a rotating table which rotates the relay body around a rotary shaft orthogonal to the fixing surface.
In this configuration, after the thin section floating on the water surface is scooped up on the fixing surface of the relay body in a state where the relay body is held by the holding portion, the relay body is set on the rotating table. In addition, after the relay body is rotated around the rotary shaft, the rotary body is delivered to the substrate. Accordingly, since a relative direction of the thin section with respect to the substrate can be set, it is possible to place the thin section in a predetermined direction on the substrate.